After a while of playing, I was able to simplify the mechanics down to somewhat a science.
Every time a level is completed: Upgrade Bravery
If Bravery isn't an option, upgrade Movement Speed
Sword Speed seems to do very little
Spawn Time seems to only reduce lag
To defeat Ninjas: Rush and slash
To defeat Aliens: Try to avoid getting hit then rush them after they fire
To defeat Executioner: Come up from below
Other than that, interesting graphics, would have been a 4 star rating if there was some sort of an intro that at least said she was put into her room.